Hidden car theftproof alarm system

The utility model discloses a hidden car theftproof alarm system, including switch S1, diode D1, diode D2, unidirectional thyristor Q1 and loudspeaker B, switch S1's the one end U1 that connects, diode D1's positive pole is connected to switch S1's the other end, diode D1's negative pole connecting resistance R1 and diode D2's negative pole, resistance R1's other end connection electric capacity C1, electric capacity C2, resistance R2 and loudspeaker B and ground connection, electric capacity C1's other end connecting resistance R2's the other end, diode D3's positive pole and triode T1's projecting pole. The utility model discloses hidden car theftproof alarm system circuit structure is simple, components and parts are few, adopts and installs in the inboard gate controlled switch conduct source of triggering of door, will trigger the alarm sound warning in case the door is opened, and the circuit adopts no chip structure, and interference immunity is strong, and is with low costs and small, consequently conceals effectually.